Abstract: A backlight unit includes a light guide panel where a holographic pattern is formed. A point light source emits light to an edge of the light guide panel. A refractive member is provided between the point light source and the light guide panel and reduces an azimuth angle of light incident on the light guide panel. The refractive member includes, from an optical axis of the point light source, a light transmission zone transmitting light as it is, a blaze zone where a blaze pattern having a saw-toothed shape in which one surface near the optical axis and substantially parallel to the optical axis is formed, and a prism zone where a triangular prism pattern is formed. The backlight unit may further include a diffusive member diffusing light emitted from the point light source to be incident on the refractive member.

Abstract: A backlight unit includes a point light source emitting light and a light guide panel including a holographic pattern formed to have a concentric circle shape having a center at the point light center. Thus, since the incident azimuth angle of light incident on the holographic pattern can be made constant, an efficiency of light exhausted through the light exhaust surface can be improved. Also, since the distribution of the exhaust azimuth angle of the exhaust light can be made uniform, a uniform brightness can be obtained from the exhaust surface.

Abstract: An illumination apparatus for planar display devices, including an optical element for making light travel parallel to an optical axis, is provided. The illumination apparatus includes a dot light source for radiating light, and a light guide plate having the optical element. The optical element is composed of a first refraction facet, which is adjacent to the dot light source and increases the emission angle of the light, and a second refraction facet, which is isolated a predetermined distance from the first refraction facet while facing the first refraction facet and reduces the emission angle of the light. In this structure, the light travels parallel to the optical axis In the illumination apparatus, the emission angle of incident light is reduced, preferably, the light travels parallel to the optical axis.

Abstract: An optical scanning unit with a rotatable hologram disc, including a light source, a rotatable hologram disc provided with a plurality of holograms, the holograms being formed concentrically along a radial direction to diffract a beam emitted from the light source by multiple steps, a reflecting member that reflects the beam emitted from the light source and diffracted by one of the holograms into another hologram, and a fixed hologram correcting the diffracted beam incident through the rotatable hologram disc to focus it on a scanning object. In the optical scanning unit, the light passes through the plurality of holograms formed along a radial direction of the rotatable hologram disc so that a scan width can be extended without reducing a scan speed of the optical scanning unit.

Abstract: A micromirror driver for simultaneously and independently controlling a resonant frequency and an amplitude of a micromirror. A micromirror having a plurality of grooves is supported in rotation by an elastic body. Base electrodes having a comb shape are affixed to the grooves and along an edge of the micromirror. A plurality of driver electrodes also having a comb shape are respectively engaged with the base electrodes in a gear like arrangement to electrostatically interact with the micromirror in response to applied voltages. An amplitude and a frequency of the micromirror are controlled by varying a magnitude or a waveform of one or more electrode voltages or by varying a phase between voltages applied to at least two electrodes. Accordingly, greater driving forces, a larger rotation angle of the micromirror, and independent control of amplitude and resonant frequency of the micromirror are obtained.

Abstract: A stereoscopic display device for compositing and reproducing a plurality of images on a three-dimensional space. The stereoscopic display device includes one or more image sources, a beam splitter, and a holographic optical element, wherein the beam splitter and the holographic optical element are configured to project an image from each image source onto a different space.

Abstract: An appartatus for balancing a rotating member capable of preventing lubricity between balls from being reduced, and of enhancing balancing efficiency thereof. The rotational center of a turntable is the same as the center of the rotating member. A groove having a predetermined depth and a predetermined width is formed along the circumference of the turntable. A plurality of balls including first balls and second balls formed of different materials are alternately disposed in the groove. The first balls and the second balls may have different diameters.

Abstract: An optical scanning apparatus which is improved in color registration by reducing bow of a scan line which is formed on a photosensitive medium. A plate having a slit with a width appropriate for a spot size of a scan line and a length corresponding to a predetermined scanning length is interposed between the photosensitive medium and a spot forming apparatus. A light source emits a laser beam, a rotary polygonal mirror reflects light from the light source while being rotated, f-&thgr; lenses cause the light reflected from the rotary polygonal mirror to form a proper spot, and a reflecting mirror disposed on an optical path between the f-&thgr; lenses and the photosensitive medium directs the spot toward the photosensitive medium. The slit plate passes a portion of the spot to uniformly form the scan line.

Abstract: An optical scanning unit with a rotatable hologram disc, including a light source, a rotatable hologram disc provided with a plurality of holograms, the holograms being formed concentrically along a radial direction to diffract a beam emitted from the light source by multiple steps, a reflecting member that reflects the beam emitted from the light source and diffracted by one of the holograms into another hologram, and a fixed hologram correcting the diffracted beam incident through the rotatable hologram disc to focus it on a scanning object. In the optical scanning unit, the light passes through the plurality of holograms formed along a radial direction of the rotatable hologram disc so that a scan width can be extended without reducing a scan speed of the optical scanning unit.

Abstract: A beam scanning system including: a light source; a deflection disc rotatably installed over the light sources and having a hologram pattern on each of the upper and lower surfaces thereof, for diffracting beams emitted from the light source; and a plurality of mirrors for reflecting beams that have been diffracted by the deflection disc, to change the diffracted paths of the beams. Each of the upper and lower hologram patterns is formed with a low density relative to a one-sided hologram pattern.

Abstract: A diffractive deflection beam scanning system including: a plurality of light sources; a deflection disc rotatably mounted over the light sources, having patterns capable of diffracting and deflecting beams emitted from the light sources; a plurality of first reflecting mirrors for changing the traveling paths of beams diffracted and deflected by the deflection disc; a plurality of second reflecting mirrors for reflecting the beams reflected by the first reflecting mirrors in a beam scan direction, wherein the light sources are disposed in a straight line along a bisecting line of the deflection disc, perpendicular to the beam scan direction, and the second reflecting mirrors are arranged over the center of the deflection disc at different heights.

Abstract: A laser scanning unit (LSU) in a structure capable of radiating heat generated by a light source. The LSU includes at least one light source, a driving source for providing rotational force, and a deflection disk installed on a rotary shaft of the driving source, for diffracting and deflecting light incident from the light sources. The deflection disk has at least one radiating portion which is depressed in and/or protrudes from the surface of the deflection disk facing the light source and induces air flow by contact with air, such that the heat generated by the light sources is radiated by the air flow induced due to the radiating portion.

Abstract: A multi-laser scanning unit (LSU) in which scanning lines incident parallel onto a photoreceptor have the same scanning direction. The multi-laser scanning unit includes: a driving source for providing a rotatory force; a deflection disk installed around a rotary shaft of the driving source having a plurality of sectors each with a hologram pattern for diffracting and deflecting incident light, for scanning light through rotation; a plurality of light sources installed facing one surface of the deflection disk for irradiating a plurality of light lines onto predetermined points of the deflection disk; and a light path changing portion for changing traveling paths of the plurality of scanning lines formed by the rotation of the deflection disk, wherein the plurality of light sources are arranged such that two incident points which are the farthest from each other among the plurality of incident points formed on the deflection disk form 180° with the center point of the deflection disk.

Abstract: A flow control valve for allowing the flow to be controlled on a proportional basis using a direct current(DC) motor thereby improving the flow control function. The flow control valve is constructed in a manner that a valve housing having a guide space and an inlet and an outlet is formed on the both sides of the valve housing, the inlet and the outlet being in communication with each other through the guide space. A spool is installed inside the guide space of the valve housing and up/down movably coupled therein so as to control the opening of the outlet. A spool guide is placed on the upper side of the guide space passing through liquified coolant by moving up/down along with the spool. A elastic support elastically supports the spool guide to one direction. A sealing member prevents the leakage of liquefied coolant by surrounding the spool on the lower side of the valve housing. A driving mechanism moves the spool up/down by use of a DC motor.

Abstract: A multi-laser scanning unit (LSU) in which scanning lines incident parallel onto a photoreceptor have the same scanning direction.

Abstract: A laser scanning unit in which a digital micro mirror device is used as a laser beam deflecting device and which is used in a laser printer, a facsimile unit, and the like. The laser scanning unit according to the present invention includes a laser diode for emitting laser beams, a photo-sensitive drum for receiving the laser beams emitted by the laser diode, and a deflecting device which is disposed between the laser diode and the photo-sensitive drum, for deflecting the laser beams toward the photo-sensitive drum. The deflecting device comprises a reflecting member for reflecting the laser beams emitted from the laser diode toward the photo-sensitive drum at a predetermined angle, a rotating member for rotating the reflecting member at a range of predetermined angles, and a supporting member for supporting the reflecting member so that the reflecting member can be rotated.

Abstract: A hemispherical bearing apparatus includes a MoS.sub.2 layer formed to a predetermined thickness on the surface of a hemispherical recessed portion formed in a bushing or on the surface of a hemispherical member opposed to the recessed portion. The hemispherical bearing apparatus is capable of enhancing the productivity and reducing the fabrication cost. The method for forming the MoS.sub.2 layer may vary with the material of the bushing and the hemispherical members. The MoS.sub.2 layer may be applied by a coating technology or an impregnating technology.

Abstract: A clothes washing machine has a motor which includes a stator, and a rotor disposed around the stator. The rotor includes a disk-shaped plate having radial blades disposed on an upper surface thereof. The blades are situated beneath the stator and generate a flow of turbulent cooling air along the stator in response to rotation of the rotor.

Abstract: A laser scanning unit includes an emitting portion for emitting laser beams, a deflecting portion having a plurality of mirror surfaces at its side portions to deflect the laser beams upon a predetermined position of a pickup surface by rotation of a predetermined speed, and a pickup portion for scanning the laser beams deflected by the deflecting portion into the pickup surface. A rotative noise reducing portion is formed at a plurality of edges formed by the plurality of adjacent mirror surfaces of a polygon mirror which acts as the deflecting portion. Preferably, the rotative noise reducing portion includes at least one air groove at the portion where the mirror surfaces connect, so as to be formed around the edges of the mirrors. Thus, it is possible to reduce the pressure difference between the mirror surfaces with the air groove, thereby reducing noise during rotation of the polygon mirror.

Abstract: A washing machine includes a water tub, a spin basket mounted inside the water tub, a pulsator mounted in the spin basket, a reversible motor mounted under the water tub for driving the pulsator and spin basket, and a damping device for damping external impacts applied to the motor. The damping device is mounted to an underside of the motor and is received in a recess formed in an upper end of a cushioning member disposed beneath the machine during shipment to stabilize the motor.